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/*
* Initialization stuff - taken from hermit
* (C) Copyright 2005 Rowel Atienza <rowel@diwalabs.com>
* Armadillo board HT1070
*
* See file CREDITS for list of people who contributed to this
* project.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
* MA 02111-1307 USA
*/
#include <config.h>
#include <version.h>
/* some parameters for the board */
/* setting up the memory */
#define SRAM_START 0x60000000
#define SRAM_SIZE 0x0000c000
.globl lowlevel_init
lowlevel_init:
mov r0, #0x70 /* 32-bit code + data, MMU mandatory */
mcr p15, 0, r0, c1, c0, 0 /* MMU init */
mov r0, #0
mcr p15, 0, r0, c7, c7, 0 /* flush v3/v4 cache */
mcr p15, 0, r0, c8, c7, 0 /* flush v4 TLB */
mov r0, #0x80000000 /* I/O base */
mov r1, #0x6 /* CLKCTL_73 in SYSCON3 */
add r2, r0, #0x2200 /* address of SYSCON3 in r2 */
str r1, [r2] /* set clock speed to 73.728 MHz */
mov r1, #0x81 /* 64KHz DRAM refresh period */
str r1, [r0, #0x200] /* set DRFPR */
mov r1, #0x500 /* permanent enable, 16bits wide */
add r1, r1, #0x42 /* 128Mbit, CAS lat = 2 SDRAM */
add r2, r0, #0x2300 /* load address in r2 */
str r1, [r2]
mov r1, #0x100 /* SDRAM refresh rate */
add r2, r0, #0x2340 /* load address in r2 */
str r1, [r2]
mov sp, #SRAM_START /* init stack pointer */
add sp, sp, #SRAM_SIZE
/* everything is fine now */
mov pc, lr
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